6T40/6T45 - Automatic Transmission
DTC P2723 or P2724
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC P2723
- Clutch Pressure Control (PC) Solenoid 5 - Stuck Off
DTC P2724
- Clutch Pressure Control (PC) Solenoid 5 - Stuck On
Diagnostic Fault Information
The following fault table gives examples of how hydraulic circuit problems and malfunctioning hard parts affect the transmission operation.
Circuit/System Description
The clutch pressure control (PC) solenoid 5 is part of the control solenoid (w/body and TCM) valve assembly. The control solenoid (w/body and TCM) valve assembly has no serviceable parts. The PC solenoid 5 is a normally high-pressure control solenoid which provides fluid pressure to the 1-2-3-4 clutch regulator valve. The TCM controls the solenoid pressure by regulating the exhaust fluid. When the TCM commands the solenoid off, the exhausting fluid is stopped and the 1-2-3-4 pressure is high. When commanded on, the clutch PC solenoid 5 regulates the amount of exhausting transmission fluid. Solenoid power is supplied by the TCM through a high side driver (HSD). The HSD protects the circuits and components that the TCM powers. Should the circuit overload the driver will shutdown. After the overload is removed the HSD reset. The TCM calculates gear ratio based on data from the automatic transmission input speed sensor (ISS) and the output speed sensor (OSS). The TCM compares the known transmission gear ratio to a calculated gear ratio for each commanded gear.
Conditions for Running the DTC
P2723
* No ISS DTCs P0716 or P0717.
* No OSS DTCs P0722 or P0723.
* No IMS DTCs P1825 or P1915.
* The transmission input shaft speed is 60 RPM or greater.
* 1-2-3-4 clutch is commanded ON.
P2724
* No ISS DTCs P0716 or P0717.
* No OSS DTCs P0722 or P0723.
* No IMS DTCs P1825 or P1915.
* The transmission output shaft speed is 200 RPM or greater.
* 1-2-3-4 clutch is commanded OFF.
Conditions for Setting the DTC
P2723
The TCM detects an incorrect on-coming clutch gear ratio, or flare, when the 1-2-3-4 clutch is commanded ON for 4.0 seconds and the transmission input shaft speed is 33 RPM or greater from the anticipated input shaft speed.
P2724
The TCM detects an incorrect off-going clutch gear ratio, or tie-up, when the 1-2-3-4 clutch is commanded OFF for 1.2 seconds and the transmission input shaft speed is 40 RPM or less from the anticipated input shaft speed.
Action Taken When the DTC Sets
* DTCs P2723 and P2724 are Type A DTCs.
* The TCM freezes transmission adaptive functions.
* DTC P2723 defaults to Reverse, Park, Neutral, 5th, or 6th gear.
* DTC P2724 defaults to Reverse, Park, Neutral, 1st, or 2nd gear.
Conditions for Clearing the DIC/DTC
DTCs P2723 and P2724 are Type A DTCs.
Diagnostic Aids
P2723
DTC P2723 detects a neutral gear when the 1-2-3-4 clutch in enabled for 2nd and 6th gear.
P2724
DTC P2724 detects a clutch tie-up when the 1-2-3-4 clutch in on-coming.
* When attempting to set transmission performance DTCs, observe the Freeze Frame and Failure Records to assist in duplicating the failure conditions.
* Use the scan tool to view the PC sol. 5 status and refer to the Transmission Fluid Pressure Switch Logic table to determine when a PC solenoid 5 switch should be active or inactive for a given gear. This will help to determine if the hydraulic circuit is functioning and if the PC solenoid or the valve train is in an incorrect position.
Reference Information
Schematic Reference
* Drive Range, First Gear (Drive Range, First Gear)
* DTC P2723 or P2724
* Drive Range, Third Gear (Drive Range, Third Gear)
* Drive Range - Fourth Gear (Drive Range, Fourth Gear)
* Drive Range, Fifth Gear (Drive Range, Fifth Gear)
* Drive Range, Fifth Gear Default (Drive Range, Fifth Gear Default)
* Drive Range, Sixth Gear (Drive Range, Sixth Gear)
Connector End View Reference
Component Connector End Views
Description and Operation
* Transmission General Description (Transmission General Description)
* Transmission Component and System Description (Transmission Component and System Description)
* Electronic Component Description (Electronic Component Description)
Electrical Information Reference
* Circuit Testing
* Connector Repairs
* Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Special Tools
* DT-48616 Control Solenoid Test Plate
* DT-48616-10 Adapter Harness
Circuit/System Verification
1. Perform the Transmission Fluid Check (Transmission Fluid Check) .
2. Operate the vehicle in drive with the calculated throttle position greater than 15 percent to obtain 72 km/h (45 mph) and achieve 5th gear. Perform this maneuver 2 times.
• If the DTC resets, go to Circuit/System Testing.
3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
1. Perform the Line Pressure Check (Line Pressure Check) .
• If the pressure is out of specification, correct this concern first.
2. Perform the Control Solenoid Valve and Transmission Control Module Assembly Cleaning (Control Solenoid Valve and Transmission Control Module Assembly Cleaning) and retest the DTC as outlined in the Circuit/System Verification steps.
• If the DTC resets, continue on with testing.
3. Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection (Control Solenoid Valve and Transmission Control Module Assembly Inspection) .
• If a concern is found, repair or replace the control solenoid (w/body and TCM) valve assembly.
4. Perform the Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test (Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test) .
• If the solenoid is found to be leaking or stuck closed, replace the control solenoid (w/body and TCM) valve assembly.
5. Inspect the control valve lower body assembly for sticking valves, damage, scored bores, or debris.
• If a concern if found in the valve body, repair or replace the valve body as necessary.
6. Inspect the 1-2-3-4 clutch assembly for damage.
• If a concern is found in the 1-2-3-4 clutch assembly, repair or replace as necessary.
Component Testing
Operating the transmission under the following conditions will verify that the PC solenoid or a portion of the hydraulic control circuit is not functioning as it should.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Important: Before replacing the TCM, perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection (Control Solenoid Valve and Transmission Control Module Assembly Inspection) .
* Refer to Control Module References for control solenoid (w/body and TCM) valve assembly replacement, setup, and programming.
* Perform the Service Fast Learn Adapts (Programming and Relearning) following all transmission related repairs.
* Perform the:
- Internal Components Removal (Overhaul)
- Low and Reverse and 1-2-3-4 Clutch Housing Disassemble (Overhaul)
- Low and Reverse and 1-2-3-4 Clutch Housing Cleaning and Inspection (Overhaul)
- Low and Reverse and 1-2-3-4 Clutch Housing Assemble (Overhaul)
- Low and Reverse and 1-2-3-4 Clutch Housing, and 1-2-3-4 Clutch Plate Installation (Overhaul)